Dental Pulp Inflammation Initiates the Occurrence of Mast Cells Expressing the α1 and ß1 Subunits of Soluble Guanylyl Cyclase.

The binding of nitric oxide (NO) to heme in the ß1 subunit of soluble guanylyl cyclase (sGC) activates both the heterodimeric α1ß1 and α2ß1 isoforms of the enzyme, leading to the increased production of cGMP from GTP. In cultured human mast cells, exogenous NO is able to inhibit mast cell degranulation via NO-cGMP signaling. However, under inflammatory oxidative or nitrosative stress, sGC becomes insensitive to NO. The occurrence of mast cells in healthy and inflamed human tissues and the in vivo expression of the α1 and ß1 subunits of sGC in human mast cells during inflammation remain largely unresolved and were investigated here. Using peroxidase and double immunohistochemical incubations, no mast cells were found in healthy dental pulp, whereas the inflammation of dental pulp initiated the occurrence of several mast cells expressing the α1 and ß1 subunits of sGC. Since inflammation-induced oxidative and nitrosative stress oxidizes Fe2+ to Fe3+ in the ß1 subunit of sGC, leading to the desensitization of sGC to NO, we hypothesize that the NO- and heme-independent pharmacological activation of sGC in mast cells may be considered as a regulatory strategy for mast cell functions in inflamed human dental pulp.

Metastatic Pancreatic Neuroendocrine Tumor Mimicking Interstitial Lung Disease Diagnosed by Transbronchial lung biopsie: A Case Report.

Pancreatic neuroendocrine tumors (PNETs) are rare malignancies characterized by insidious onset and mostly present with metastasis at the diagnosis. Lung metastasis manifesting diffuse ground-glass opacity is a very rare pattern that is difficult to distinguish from nonmalignant pulmonary diseases. Recognition of this atypical metastases pattern and avoidance of this potential pitfall are crucial. We report a unique case of the Metastatic Pancreatic Neuroendocrine Tumor Mimicking Interstitial Lung Disease diagnosed by transbronchial lung biopsie. Keywords: Neuroendocrine Tumor, Metastasis, Groundglass opacity, interstitial lung disease.

Mandibular bone changes in sickle cell anemia: fractal analysis.

OBJECTIVES: The radiographic changes of mandibular bone texture was evaluated in patients with sickle cell anemia (SCA) and healthy controls. Fractal analysis was employed. STUDY DESIGN: Thirty-five individuals (age range 11 to 40 years) who had been diagnosed as having homozygous SCA were enrolled as the patient group. Twenty-six healthy individuals within the same age range constituted the controls. Panoramic radiographs of all subjects were obtained using analog film and then digitized. All procedures for calculation of the fractal dimension were performed using Image J version 1.34s software (National Institutes of Health, Bethesda, MD). ROIs were selected as 64 x 64 pixel-sized squares, which were located between the first molar and second premolar teeth of the right mandibular segment. The fractal dimension (FD) was calculated by using the box-counting function. FD values of SCA and control groups were analyzed statistically by using Student t tests; alpha was set at 0.05. RESULTS: The FD values for SCA patients were different from those of the healthy controls (mean FD SCA = 1.6855; mean FD controls = 1.7196); with a significance of P = .050. FD values for the SCA group had higher standard deviations (SD) than was the case for the healthy controls (SCA SD = 0.0859, control SD = 0.0459). When individuals were subclassified according to their age being younger than 20 or 20 years and over, the mean FD values of patients under 20 years of age were significantly lower than both the SCA patients over 20 years of age and all of the healthy controls (P < .05). CONCLUSION: SCA patients under age 20 years showed lower FD values than the controls and this finding pointed to scarcity of trabecular bone in this group.